<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>隐藏搜索框</title>
    <link rel="stylesheet" href="./demo.css">
</head>
<body>
    <div class="container">
        <input type="text" class="input" placeholder="Search...">
        <button class="btn">S</button>
    </div>
    <script src="./demo4.js"></script>
</body>
</html>